Semiconductors are very important goods necessary in various industries. A semiconductor chip, which is a typical product thereof, is produced, for example, by slicing a silicon monocrystal into a given thickness to produce a silicon wafer, and then forming various integrated circuits and the like on this silicon wafer.
In order to form integrated circuits and so on of this type, it is necessary to conduct a process of applying a photosensitive resin onto the silicon wafer, exposing the resin to light, developing the exposed resin and then subjecting the resultant to post-curing and sputtering, to form a conductor layer. For this purpose, it is necessary to heat the silicon wafer.
As this heater for heating the silicon wafer and the like, a ceramic heater is used. JP Kokai Hei 11-40330 and so on disclose heaters using a carbide ceramic or a nitride ceramic.